How does mutualism compare with commensalism

Mutualism means that two animals interact with each other and both benefit from it. For example, pilot fish hang around sharks. The fish clean the sharks, while the sharks offer protection for fish.

Commercialism, meanwhile, is an interaction between two species where one species benefits while the other is not harmed nor does it get benefits. For example, tree frogs use trees as protection , and this benefits the frogs but not the tree. But it does not harm the tree, so the frog benefits but the tree is not hurt nor benefited.

there really is life in the deepest part

unicellular organisms, like bacteria, are able to perform all life functions within one single cell. multicellular organisms need many different types of cells to carry out the same life processes. each of these special types of cells has a different structure that it perform a specific function.